With SPIDER’s flight complete, the record of its observations resides in the payload’s data storage drives. SPIDER records data too quickly to transmit back via satellite, so the only way to get its valuable data back is by recovering those drives from the payload. The Antarctic Treaty also requires us to recover SPIDER’s hardware from the ice for environmental reasons.
All of this means: we need to send a team to SPIDER’s landing site. And yesterday we did!
Given SPIDER’s location, recovery flights to the SPIDER payload must be staged from South Pole Station. Canadian airline Ken Borek Air services such remote locations using two types of small aircraft: Twin Otter (DHC-6) and Basler (BT-67, a modified DC-3). These planes and their adventurous pilots can land in terrain and weather inaccessible to larger craft. They can carry both passengers and cargo, with quantities of each depending on distance and fuel allocation.
NSF and NASA/CSBF take advantage of a variety of satellite imagery to perform a first evaluation of the landing site. On January 10th the flight crew performed an initial reconnaissance flight to get eyes on the payload and terrain. The report back was excellent: SPIDER is largely intact, and the terrain looks favorable for landing and taxiing near the payload. Based upon this, LDB/CSBF put in a request for NSF to support a series of recovery flights; after a few days waiting for other operations to complete, we were given the go-ahead! Now the team gathers tools and waits for good weather…
Recovery in a Nutshell
SPIDER is too large to fit into the cargo holds of these aircraft, so the recovery team must cut up SPIDER’s carcass and bring it back in pieces. We on the science team are responsible for writing a procedure for this: what are the highest-priority items to recover, where to cut the big components, etc. The top-priority items are the data vaults: a set of solid-state storage and helium disk drives that hold multiple redundant copies of SPIDER’s data. Also high on the priority list are NASA SIP electronics box (located under the payload deck) and SPIDER’s major flight electronics, all accessible on the payload deck and on the belly of SPIDER’s cryostat. We labeled these top-priority items in black marker before launch, even marking up the deck to show the easiest places to cut.
With the SPIDER and CSBF teams sent off-continent so early this year, recovery work stretches the few remaining people extremely thin. LDB team members Scott Battaion (CSBF) and Rose McAdoo (ASC) went to Pole to support recovery, along with SPIDER team member Sasha Rahlin (already there for work on the South Pole Telescope). Along with the flight crew, this group must make several trips to the payload for long hours of work at wind chills of -60F. Upon return to Pole, they will pack up the high-priority cargo for return to North America. Depending on how many flights the weather permits this season, they may also have to judge when to stop the recovery process, and prep the remainder of the payload for the long winter.
First Recovery Flight
After a few days of poor weather, the team made their first trip out to the payload on January 21st. After a hard day’s work, they managed to return all of SPIDER’s high-priority data and electronics to the South Pole – a huge success!
SPIDER’s data now begins a long journey back to North America. Along the way we make copies, both to secure against damage or loss in shipping, and to distribute among the various collaborating institutions. One copy of the data drives will be made at Pole. The drives will then head to McMurdo and on to Christchurch, where a SPIDER team member will make additional copies for distribution back home. Then the real fun begins, and we see what the data can tell us about our universe.